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SODA, SALT, AND WATER BATTERY EXPERIMENT (:- NATASHA EPSTEIN'S REPORT.

ABSTRACT:

Our experiment was a test to see if we could create a "better battery". To attempt to create this battery we decided to use a combination of water, soda, metal and salt. We mixed the soda and salt in a beaker and measured the voltage and current. We slowly diluted the solution of salt and a soda (sprite and coke) with water, changing the concentration each time. We believed from the very beginning that if the solution had more soda and salt then it would have a higher voltage and current. Therefore, we believed that the more diluted solutions would have a lower voltage and current. We were able to discover valid voltages and currents for each concentration of our solutions. We found out that concentrations of coke and water with more water tended to have a lower voltage; however there were some special cases. In then end, though, we had enough numbers to compare the data to our prediction of outcome and come up with a conclusion.


INTRODUCTION:

The purpose of our experiment was to see if we could create a "better" battery. We were all trying to create a BIGGER and STRONGER battery than the standard 1.5V ones we have today. This assignment influenced us to open our minds through creating our own experiments, and relating how WE saw science to how it was really used in everyday life.

In our experiment we investigated many variables. However, to make the experiment CONTROLLED we needed to only have ONE variable be independent. We had variables of: amount of salt, amount of total solution, the sizes of metal, the concentrations of soda, the types of soda, and the types of metal. The dependent ones consisted of all the above, except one: the concentrations of soda to water. This meant that throughout our experiment we were constantly changing the concentration of soda to water; for example perhaps: 50% soda-50% water, 20-80%, 40-60%, etc.

Using this variable as a guide to our experiment and the results we came up with some expectations/ predictions of the outcomes. We predicted that the solutions with a higher concentration of salt and a soda would be higher in voltage, and create a stronger battery. We had learned in our original experiment where we created a "salt water battery" that salt influenced the voltage of the battery. We used the same amount of salt in both mixtures of 300mL pure soda- and believed that the salt would bring the voltage up. However, since the salt was a dependent variable, we looked a lot at how the soda would affect the voltage. I believed that with the soda having a lot of chemicals in it, including carbon dioxide, it would influence a higher voltage- especially as it was mixed with salt (which made it fizz).

Check out file "predict" at the bottom of the page.

PROCEDURE:
For our experiment we are using different types of soda (Coke and Sprite) to help us measure voltage.

In our experiment we tested the amount of current and voltage in our circuit by using soda instead of water and changing the concentration of the soda. We started with 300ml of soda in which we dissolved 9.77 grams of salt in. Inside the beaker that held the soda and salt we inserted to pieces of metal that were congruent in sizes but were different materials, one was iron and the other was cooper (at least it is to my understanding). The two pieces of metal were not touching and there was one endpoint of a wire on each of the pieces of metal. Each metal had a different wire connected to it that we connected to a machine that told us the current and voltage of our circuit. When finish this we filled up a cup with 300ml of water, added the same amount of slat as the first experiment and we took the same measurements. Then we only fill the beaker with 250ml of water and added 50ml of the soda that we used in the first test and we did the same tests. We kept doing this but every time fills up the beaker with 50ml of water then the last time. Until we got to 150ml.


GATHERING MATERIALS:

The materials we will be using for our experiment include:
- 2 large beakers
- 1 stirring stick
- Salt (and a spoon to add it with)
- Copper and Aluminum metals
- Soda: Sprite and Coke (300mL)
- Alligator clips with wires
- Voltage and Current Measuring Machine Thing (:
- Digital Balance to weigh the salt.



STEPS OF PROCEDURE:

Step 1: We take 300mL of Sprite and 300mL Coke and put them into two separate beakers.
Step 2: Put and equal sized piece of the metals in each beaker with the soda.
Step 3: Use digital balance to weigh salt (9.68g) and then add it to each beaker and mix until all the salt is dissolved.
Step 4: Measure the voltage and current of each beaker of "pure" soda. By:
a. Attaching double ended alligator clip wires to each metal.
b. Attach the other end of the wire (another clip) to the clip on the voltage/current measuring device.
c. Twist knob on device to amps (current) and measure, and then Volts (voltage) and switching the red cord back and forth each time.
Step 5, 6, 7: Water down the sodas each in the same 3 ways and measure voltage and current each time:
a. 250mL water: 50mL soda
b. 150mL water: 150mL soda
c. 200mL water: 100mL soda



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EVALUATION:

We had expected, as I mentioned earlier, that the voltage would rise as the concentration of salt and soda went up in the solutions. To our surprise we found that in the first 3 coca cola solutions (300, 150, 100mL of coke) the voltage decreased as the amount of soda with salt went down. However, on the 4th solution with only 50mL of soda, and 250mL of water we found that the voltage jumped back up higher that the solution with 150mL soda and 150mL water ! We were quite surprised, and then looked at the currents. We noticed that the current slowly INCREASED as more water was added. These first discoveries had proved our original hypothesis wrong, at least for the coca-cola and salt solutions. In the Sprite, salt, and water solutions our results came out a little differently. Again, we had expected higher voltages when there was more soda and salt. However, we found that the voltage always STARTED higher, but as the numbers on the measuring device slowly decreased they always seemed to stop at just about the same number. The current of these solutions, however, again rose as more water was added. Joey and I were a bit disappointed. I was disappointed because our results seemed quite similar to each other. Joey, however, was disappointed because she wanted something to explode. (:

Our experiment had some strengths, but also weaknesses. Its strengths were that it was unique, and no one was doing the same thing as us in our class. Also, it was strong because it was so simple- we had thought out our dependent and independent variables so that it was a controlled experiment. However, we came to a bit of a problem during our experiment that we hadn’t quite thought through. We wanted to dilute the soda, but we realized that if we poured water into the beaker, and poured the soda and salt solution out we wouldn’t have the same amount of salt in each test. However, we figured that if the salt was saturated all over the soda in the beaker, then it shouldn’t be a problem- because the proportions would be the same, for example- if there’s 20% of soda going in with the water, 20% of the salt goes with it. However, we never really had the chance to go through with totally saturating the soda with salt, so we just went with what we had. Also, we didn’t necessarily keep the metals in the beakers the exact same distance apart each test. We didn’t think that it would make much of a difference to our experiment. However, after reading other groups’ reports we noticed that it could impact the voltage and current. If I ever did this experiment again I would want to measure the distance of the metals, or possibly create a device to hold them the same distance apart as I do my experiment. Also, I would think through ALL of the possible kinks, and not begin my experiment before thinking about the next steps following it.

From my results, I can conclude that maybe the voltage of our battery was not as high as we had hoped. However, the current was at a pretty good level in some of our tests, and all or our measurements were pretty certain and precise. This “better battery” Joey and I tried to create probably needed a bit more salt used to heighten the voltage and current. Although the battery did not necessarily come out “better” the variable we used was definitely a good one to try. I would recommend that to control this variable it’s always good to try a lot of different things. If you try many different concentrations then your results will be more expansive, and help you get a better look at all of the possibilities of voltages and currents.

Joey's' evalution

Our data does not really tell us if want I had expected is correct it show makes us think of more questions about the circuit to truly understand soda circuit we would have to do so many more experiment. I think that when I thought of this we left a lot of holes in the plan. An example of this is that I didn’t think about the gas inside the soft drink. What I predicted did happen about it didn’t really make much sense. I think to understand this entirely we would have to test all the ingredients that make up the soft drink so we can find out which one is creating the whack out results.



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EXPECTATIONS:

[[image:file/view/predict.jpg width="505" height="307"]]

GRAPHS:




TABLES/DATA:




Amount of coke
Amount of water
Current
Voltage
300ml
0ml
9.2>1.5
0.54<0.76
50ml
250ml
5.7>1.9
0.481<538
100ml
200ml
3.6>1.9
0.47<0.511
150ml
150ml
8.2>1.7
0.498<0.520








Amount of sprite
Amount of water
Current
Voltage
300ml
0ml
4.2>0.7
0.48<0.51
50ml
250ml
3.2>4.0<1.6
0.505>0.515
100ml
200ml
4.0>1.5
0513>0.472<0.503
150ml
150ml
5.2>1.4
0.457<0.500